1. Field of the Invention
The invention relates to a system for transmitting information between two different rooms, comprising signal transmitting means installed in one room and signal receiving means installed in the other room.
Wireless information transmission is increasingly used in houses; one may think in this respect of wireless telephones, remote control for audio and video equipment, wireless headphones, baby phones and so on.
2. Description of the Related Art
A characterizing feature for all these known systems is the use of radio waves, infrared light or ultrasonic sound for transmitting information. A large drawback to the use of infrared light and ultrasonic sound is that such signals cannot simply be sent from one room to another if the two rooms are separated by partitions or walls, as is the case with the rooms in a house. Partitions or walls do not pass an intensely high signal frequency, for example 60 GHz, either, which frequency may be utilized for signal transmission in the near future. Radio waves do not have this drawback, but the use thereof brings along other objections. For example, the transmitted radio waves may cause interference to other equipment in the house, but also outside the house and, in the case of confidential information, coding must be used to avoid third parties outside the house tapping the information; a radio connection is sensitive to external sources of interference such as the ignition of engines and, finally, there is an extensive regulation with respect to the use of various radio frequencies and there is little or no possibility of having new frequencies assigned to new applications.